The climate-conscious corpse (part 1)

“God made death so we’d know when to stop.”

-Steven Stiles


“First, it’s not a matter of if your body will produce greenhouse gases, but when and over what length of time. At one extreme, burning will release all of the greenhouse gasses immediately. At the other extreme, putting your body in a coal-forming wetland might delay the release by many millions of years. Since the problem is anthropogenic greenhouse gas emissions, the delayed release option would be the best option for addressing your concerns, since presumably anthropogenic greenhouse gas emissions won’t be a problem a few million, or even a few thousand years from now. That suggests that your best option would be to tie weights to your body and sink it deep in a cold bog (it would be best to first open up your abdominal and thoracic cavities, and also open your stomach, intestines and heart, so that there are no gas-trapping cavities that could potentially make you float).”

I miss my chats with my friend Joe Skulan. We used to talk a lot more about all manner of things twenty five years ago, before we both started families and moved away from Madison. One day back then, Joe asked me to help him prepare the fossil skeleton of a prehistoric saber-toothed cat that he wanted to mount and display at the University of Wisconsin Geology Museum. I had exactly zero paleontological knowledge or experience, but I agreed to give it a try because I liked hanging around Joe, who was and is endlessly interesting, and because I had enjoyed the introductory geology class I took in college. Joe was a patient and forgiving teacher, and it didn’t take me long to fall in love with the painstaking but exciting hands-on work and the dusty, specimen-filled museum.

The following spring, in 1988, I noticed on my walks to the museum that the grass never turned green. That summer Yellowstone National Park burned up, the Amazon rain forest was ablaze, and a little-known NASA scientist by the name of James Hansen told a Senate panel that the greenhouse effect was “changing our climate now.” The decade had already seen the four hottest years on record. I stayed on as a museum volunteer for a couple of years and got to help dig up, prepare and display the fossilized remains of several other fascinating creatures. I also got to hang out with lots of other bearded and braided folk who enjoyed drinking beer and telling stories almost as much as finding and working on old bones. I remember a conversation or two about global warming, but, like Congress, none of us did much of anything about it.

These days Joe and I don’t often see one another, but we do swap an occasional email or Facebook message. Now, as back in the ’80s, our exchanges can be a bit lopsided. That’s not because Joe is not a good listener – he is – but because he’s a polymath and generous with his knowledge. I ask lots of questions, Joe answers at length. He has degrees in biology, geology, paleontology and geochemistry and a better-than-working understanding of several other fields, including literature, art and religion. Joe also happens to be one of the most humble and hilarious guys I know. I’ve learned a lot from him, little of it having to do with paleontology.

When I decided to write about the “coolest” or most climate-friendly ways to deal with one’s mortal remains (I’ll try to avoid the term “dispose of”), I decided to contact Joe, who is back at the UW again – this time as a curator and researcher – to see if he could recommend an expert or two who could answer some technical questions for me. I knew Joe would be able to shine some light on the subject himself. What I did not know was that he would be able to answer almost all of my questions.

Fossil fuel bath

I had done a little research myself. Not enough to determine what the best choice was but enough to know what the very worst way to go was.

It would be hard to devise a more climate-unfriendly exit than the conventional American funeral and burial. Figuratively and in many cases literally, we drench our dead in fossil fuels. With respect to the literal, I’m not talking about cremation (I’ll get to that later); I’m talking about embalming and most of what comes before and after. Besides water, just about everything in embalming fluid is derived from fossil fuels. Formaldehyde is still widely used to fix and preserve body tissue short term, despite being implicated in certain types of cancers. Although the fluid morticians use to replace blood in the arterial system contains only around 5 percent formaldehyde, the fluid injected into the body cavity typically consists of 50 percent of that agent. Formaldehyde is ultimately derived from petroleum, natural gas or sometimes even coal. Ethanol, which can make up between 9 to 56 percent of embalming fluid, can be produced as either a petrochemical, through the hydration of ethylene, or via biological processes, depending on the prevailing prices of grain and feed stocks. Petroleum is also the source of hexane, one of several solvents commonly added to embalming fluid.

Of course before bodies even get embalmed (the procedure is not required by law in most places, but open-casket funerals are much more challenging without it), they are usually refrigerated, sometimes for months, and that takes electricity. Sadly, most electricity in the U.S. is still produced by burning fossil fuels — coal or natural gas. Eventually the dead are laid out in wood or steel caskets, which in their manufacture and shipping release large amounts of greenhouse gases into the atmosphere. Roughly 70 percent of the departed who were buried in the United States were laid out in these types of caskets in 2010.

Many modern cemeteries require the use of a burial vault or liner, usually made from reinforced concrete. Typically, these weigh a little over a ton. Producing 1 ton of Portland cement, the primary ingredient in concrete, releases 1 ton of carbon dioxide. Estimates vary, but cement production accounts for somewhere between 5 and 10 percent of anthropogenic CO2 emissions. Although efforts are underway to develop greener concrete, most of these processes are years if not decades from commercial viability.

Concrete vaults and liners prevent caskets from being crushed by the weight of the earth and grave-digging equipment. They minimize sinkage, making cemeteries easier to mow. All that mowing year after year uses enormous amounts of oil and emits great volumes of greenhouse gas.

Add to this the emissions resulting from the transportation of bodies to and from hospitals, funeral homes and cemeteries (almost all of which are heated, cooled and lit primarily with fossil fuel) in ambulances and hearses. Then take into account the heavy equipment used to dig most graves — usually some type of backhoe. In colder states like ours where the ground is still frozen several months of the year, earth-thawing heaters (the guys at one of our local cemeteries call their home-made contraption “the cooker”) are employed to facilitate the dig. Fuel of choice for these devises: propane, a by-product of natural gas processing and petroleum refining.

Don’t forget the grave markers; the raw stone from which these are cut and engraved is rarely mined nearby. More oil, more greenhouse gas.

Chances are your mourners will not have the eco-consciousness and emotional wherewithal to carpool to your funeral and burial, or take mass transportation to visit your grave in the future, so they will send some significant CO₂ to join you in the blue beyond.

It’s all enough to make the devil (if you still happen to believe in a literal hell) envious. Such a burial certainly will not earn you a posthumous green halo from any natural or supernatural entity.DSCF4408

18 kilograms, 4 gallons

Like most people, I hadn’t given a lot of thought to my final footprint. I assumed cremation was a fairly green choice.  It’s also a pretty popular one nowadays; about 40 percent of the dead were cremated in America in 2010.

Although choosing cremation does cut out a lot of the emissions given off by the conventional American burial, I discovered that it is far from a saintly option. The retorts (incinerators) most funeral homes and crematoriums use require about 2,000 cubic feet of natural gas and 4 kilowatt-hours of electricity per body. According to a 2009 Slate article, that produces the amount of CO2 that the typical American home generates in six days – about 250 pounds. It turns out the recently departed, still being fairly moist, do not burn easily. It’s like trying to light green wood — you are going to have add some lighter fluid or gasoline to get it going.* And it’s not just CO2 you’re sending in to the sky, it’s other powerful greenhouse gases like carbon monoxide and nitrogen oxides. Along with lots of superheated air. If you haven’t left instructions for their removal, your amalgam fillings will volatilize when burned, too, sending significant amounts of mercury into the atmosphere. That toxic metal will eventually make its way into waterways, into fish and into the still living and yet to be born, where it can wreak neurological havoc, especially in infants and children.

As far as I can determine, that Slate CO₂ figure does not include the amount of carbon given off by the corpse itself during cremation. But according to Joe, the average human body contains about 18 kilograms of carbon, which equals about 24 kg of methane or 60 kg of carbon dioxide. This is equivalent to about 4 gallons of gasoline.

“So whatever you do to reduce your personal posthumous carbon production will mean nothing if you burn more than 4 gallons of gas doing it. So even with the most fuel-efficient car you cannot be transported more than 200 miles from where you died. It also means that no heavy equipment can be used to, say, dig a grave, since transporting a backhoe to the site, having it dig and fill the grave, and transporting it back certainly will burn more than 4 gallons of gas. It seems to me that it also eliminates cremation.”

So what options is the climate-conscious corpse left with, especially since deep burial in a coal-forming wetland isn’t practical for most of us? I’ll address that question, with Joe’s help, in part 2.

*not recommended.



  1. Rick,
    I’ve not yet convinced my wife of this, but I’d like my carcass to one day be placed high up in the Baraboo Hills. Then, the turkey vultures can pick me clean, along with carrion beetles, and poop me out all over Sauk County. Next, the mice can gnaw my bones. A low impact way to close the loop on the great circle of Life and join that great compost pile in the sky.